How does CERN synchronize timing devices?

CERN's timing systems are one of the most complex things I've researched for HowStuffWorks. That's partially because there's no single system at work in all of CERN's many particle accelerators -- different installations have different requirements -- and the accuracy of the timing systems comes down to the nanosecond. Biggest surprise: Even the smallest adjustment of an antenna can impact the synchronization of timing devices.